some refactoring

client.go

@@ -7,6 +7,7 @@ import (
 type Client struct {
 	es     *elasticsearch.Client
 	config *Config
+	ch     chan Data
 }
 
 func NewClient(config *Config) (*Client, error) {
@@ -30,11 +31,14 @@ func NewClient(config *Config) (*Client, error) {
 }
 
 func (c *Client) Open() error {
-	// create a buffer channel
-	ch := make(chan Data, 1)
 
-	for index, from := range c.config.Indexes {
+	// Open a connection with ElasticSearch
-		NewWorker(c.es, index, from, c.config.BatchSize, ch)
+
+	// create a buffer channel
+	c.ch = make(chan Data, 1)
+
+	for _, index := range c.config.Indexes {
+		NewWorker(c, index)
 	}
 
 	return nil

cmd/main.go

@@ -9,8 +9,8 @@ import (
 
 func main() {
 	config := &elasticstream.Config{
-		Host:      "http://localhost:9200",
+		Host:      "http://test.urantiacloud.com:9200",
-		Indexes:   map[string]int{"users": 0, "students": 0, "teachers": 0},
+		Indexes:   []string{"IndexA", "IndexB", "IndexC"},
 		BatchSize: 10,
 	}
 

config.go

@@ -3,6 +3,6 @@ package elasticstream
 type Config struct {
 	Host string
 	// map of index name and position from where data is to be read.
-	Indexes   map[string]int
+	Indexes   []string
 	BatchSize int
 }

worker.go

@@ -1,29 +1,21 @@
 package elasticstream
 
 import (
-	"github.com/elastic/go-elasticsearch/v8"
+// "github.com/elastic/go-elasticsearch/v8"
 )
 
 type Worker struct {
-	client *elasticsearch.Client
+	client *Client
 	index  string // name of the indexes worker pulls data from
-	from   int    // from where to start read data
-	size   int    // batch size
-	buffer chan Data
 }
 
-func NewWorker(client *elasticsearch.Client, index string, from, size int, buffer chan Data) *Worker {
+func NewWorker(client *Client, index string) {
 	w := &Worker{
 		client: client,
 		index:  index,
-		from:   from,
-		size:   size,
-		buffer: buffer,
 	}
 
 	go w.start()
-
-	return w
 }
 
 func (w *Worker) start() {